Composition of matter and process of preparing the same



Patented Oct. 25, 1932 UNITED STATES PATENT OFFICE IDIUND O. EEO DE I'LOYD D. EAGEB, O1 PITTSBURGH, PENNSYLVANIA, ASSIGN- 038 1'0 AIEBIUAN TAB PBODUOTS COMPANY, A CORPORATION 01 DELAWARE COHPOBII'ION P AND PROCESS OI PREPARING THE SAME Io Drawing.

This invention relates to a composition of matter and a process of preparing the same and more part1cularly to the pre aration of plastic compositions contamlng itummous 5 materials.

It is known that rubber may readily be dissolved or dispersed in etroleum products and particularl in tars erived from petroleum or in pro ucts obtained by the dist1lla- 1 tion thereof. However, coal tar has been found to be a very poor solvent or dispersing agent for rubber.

An object of this invention is to combine the properties of bituminous materials and 1s rubber and to form a roduct which will be exceedingly useful in t e various arts.

The product of this invention comprises various combinations of bituminous materials and a rubber ingredient such as vulcanized or unvulcanized rubber, latex, iutta-percha, balata and other caoutchouc-li e materials, treated with sulphur. The particular bituminous materials which are used are petroleum tar such as water as tar coal tar such as coke oven tar; an the distillates and pitches obtained from such tars. When a coke oven tar is used it is desirable, but not necessary however, to employ one from which substantially all constituents boiling above 190 C. have been removed.

A very useful product is formed by mixing rubber with water (gas tar until a homogeneous mass is obtaine and then adding sulphur and heating until a roduct of the desired viscosity, elasticity an tou hness is obtained. This may be determined y testing cooled samples of the heated materials.

Another desirable product is obtained by includingin the above composition a coal tar such as cokeoven tar. Pitch derived from water gas tar or coal tar may be substituted for a part of or all of the coal tar. 'When these materials are included, it is preferred to first disperse rubber in water gas tar, then mix in the coal tar and/or pitch and finally Application fled July 90, 1828. Serial No. 879,878.

treat with sulphur. If the tars are first treated with'sulphur before the addition of rubber, the resulting product is not as likely to have as desirable properties as those of the product obtained in the preferred method.

The rubber, water as tar and coal tar and/or pitch are heate and stirred together until a homogeneous mass is obtained and sulphur is then added to the extent of 4 to 15% of the weight of bituminous materials with thor-. ough mixing. The reaction mixture is heated until it is found that cooled samples thereof will remainhomogeneous and have the desired degree of elasticity and toughness, the magnitude of which will of course vary with the quality and quantities of the materials used. By way of example, the following method may be em loyed in the preparation of a product of t is invention: 15 arts by wei ht of a vulcanized rubber are dissolved or 'spersed in parts by weight of water gas tar. 200 parts by weight of this mixture are added to 800 parts by weight of coke oven tar. The mixture is heated to about 180 C. with stirring and 40 parts by weight of finely divided sul hur are added over a period of about 15 minutes. The temperature of the reaction mixture is then raised to about C. for one hour, the stirring being continued throughout that time. Upon treatment of the tar and rubber with sulp ur, the latter 'brin about changes wh1ch result in the formation of a permanent solution or dispersion of the rubber. The resultin product is elastic and tough and quite un ike any of the original materials.

By the process of this invention products are prepared which have a high de e of elasticity and low thermo susceptibility and are ve useful in the manufacture of materials in which bituminous matter is employed, as for instance in insulating and road materials.

We claim as our invention:

A process comprising dissolving a rubber 90 ingredient n water gas tar, mixin coke oven tar with the resulting solution, eating the mixture to about (3., adding sulphur to the said mixture with stirring, raising the tem erature to and keeping it at about C. unti the mixturewhen cooled, remains homo neous.

n testimony whereof we have hereunto iubgcribed our names the 16th day of July,

EDMUND O. RHODES. FLOYIQ D. HAGER. 

